Kansas Nebraska Act 1854 Kansas-Nebraska Act the issue of slavery would not die In 1854, Congress pass an act where people in the area could vote on whether they wanted to be a free state or a slave state- popular sovereignty to the areas known as the Kansas and Nebraska territories. Northerners were angry because this changed the Missouri Compromise This act led to violence as pro-abolition and pro-slavery (free soilers) forces flooded Kansas to sway the vote, in what became known as Bloody Kansas. More than 200 people were killed The Kansas-Nebraska Act A Segment of: The American Civil War: The Causes of War